Kevin Kelly has written a thoughtful post FEB 07 2008

When copies are super abundant, they become worthless.When copies are super abundant, stuff which can't be copied becomes scarce and valuable.

He then lists eight reasons why people pay money for things that could be free, one of which is immediacy:

Sooner or later you can find a free copy of whatever you want, but getting a copy delivered to your inbox the moment it is released -- or even better, produced -- by its creators is a generative asset. Many people go to movie theaters to see films on the opening night, where they will pay a hefty price to see a film that later will be available for free, or almost free, via rental or download. Hardcover books command a premium for their immediacy, disguised as a harder cover. First in line often commands an extra price for the same good.